Dental mandrel



(NorModelj w. SJELLIOTT.

DENTAL MANDREL.

No. 514,882. Patented Feb. 13, 18,94.

WITNESSES.

UNITED STATES PATENT OFFICE.

WALTER S. ELLIOTT, OF SAG HARBOR,- NEW YORK, ASSIGNOR OF ONE-HALF TO JAMES W. IVORY, OF PHILADELPHIA, PENNSYLVANIA.

DENTAL MANDREL.

SPECILEIIIGA'IION forming part of Letters Patent No. 514,882, dated February 13, 1894.

Application filed April 24, 1893- Serial No. 471.548- (No model.)

To all whom it may concern.-

Be it known that I, WALTER S. ELLIOTT, a citizen of the United States, residing at Sag Harbor, in the county of Suffolk, State of New York, have invented a newand useful Improvement in Dental Mandrels, which improvement is fully set forth in the following specification, and accompanying drawings. My invention consists of a mandrel for holdmg a paper, metal, rubber or other disk, a saw, corundum stone, &c., the construction being such that the disk, &c., may be easily and quickly applied to the mandrel, steadily and firmly held thereon, and easily and quickly removed, the construction of parts being hereinafter fully set forth.

Figures 1 and 3 represent perspective views of dental mandrels embodying my invention,

the parts being shown separated. Fig. 2 represents a side elevation of the construction Fig. 1. Fig. 4 represents a side elevation of vthe construction Fig. 3, the parts being in operative conditiorn Fig. 5 represents a side elevation of another form, the nut employed therein being shown removed from the mandrel.

Similar letters of reference indicate corresponding parts in the several figures.

. paper, metal, rubber, 850., or may be of the form of a saw, corundum stone, &c., the same having an opening E centrally therein, so as to be fitted on the end of the shank, said end having a threaded opening F to receive a headed screw G, it being seen that when the collar B is drawn back, and the disk located on the shank, the screw is operated, thereby the collar is forced against the inner side of the disk as a shoulder, while the head of the screw bears against theouter side of the same, it being noticed that the disk is clamped on opposite sides by the collar and the head of the screw G, and thus it may run true and without wabbling, and will not loosen or tearout. When the screw G is properly rotated, it may be removed from the shank, and the disk displaced, as is evident.

In Fig. 5 I employ a nut H in lieu of the screw G, and form a thread J on the end of the shank, and a shoulder K back of the same, the disk being adapted to be clamped between said nut and the collar M. In this case I place the mandrel in the hand piece, and rotate the spring L down on the shank the entire length of the coil, catching it between the fingers so that the thumb and forefinger may hold the nut as'it is screwed ofi. Slip on the disk extending it on the shank to the collar M. Apply the nut by running the engine forward, grasp the spring with the fingers, and run the disk up to the nut and tighten the latter. To remove the disk, reverse the engine, always holding the spring between the fingers in such manner that the thumb and forefinger may catch the nut as it is unopenings U radiating therefrom, it being seen that when the cap is in position shown in Fig.

3, the disk may he slipped over the cap and,

reduced end of the shank, and then seated on the adjacent portion V of the shank, after which the cap is turned so as to be parallel with the disk, and rest against the outer side thereof. The spring is then turned toward the collars whereby the collars Q and P are forced against the inner side of the disk, it being evident that the disk is clamped on opposite sides by the collar P and the cap N, as will be seen in Fig. 4. It will also be noticed that the pressure of the coil 0 is powerful in its nature, owing to its action, both as a screw and a spring, and the disk will thereby be prevented from slipping. Owing to the pin or stud O the convolution of the coil which ICC is in contact with said pin, is firmly held, while the remaining convolutions between said pin and collar are free, whereby they are elastic, so that the pressure of the pin on the contiguous convolution causes said free convolutions to exert spring pressure against the collar, said pressure being greater than if exerted by a rigid screw, not or sleeve.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is-

1. A mandrel having a pin projecting from the shank thereof, a rotary coil on said shank having its convolutions engaging with said 

